Case report: hypodontia and short roots in a child
with Fraser syndrome.

Abstract:

BACKGROUND: Fraser syndrome is a rare autosomal recessive disorder
of which there has only previously been one case reported in the dental
literature. The main characteristics are cryptophthalmos, syndactyly and
genital abnormalities. Orofacial findings reported are: facial
asymmetry, cleft lip and palate, high arched palate, dental crowding,
fusion of primary teeth, dental hypoplasia, malocclusion, and
supragingival calculus. CASE REPORT: A 15 year old girl with Fraser
syndrome attended Bradford and Airedale salaried dental services
complaining of painful mandibular anterior teeth. On examination she
presented with hypodontia, shortened roots, and the mandibular anteriors
had a titanium trauma splint fixed to reduce the mobility. This had been
placed 4 years previously by a paediatric specialist. However oral
hygiene was poor around it and therefore the patient had calculus and
gingivitis. TREATMENT: The splint was removed followed by subgingival
scaling under local analgesia, fissure sealants of all posterior teeth,
regular oral hygiene instruction and scaling, and occasional use of
chlorhexidine gel. FOLLOW-UP: She has been reviewed regularly with
frequent scalings over two years. CONCLUSION: This case reports the
possibility of hypodontia and short roots being associated with Fraser
syndrome.

This case reports only the second case of Fraser Syndrome (FS) in
the dental literature, and the first with hypodontia and shortened
roots. FS is a very rare autosomal recessive multisystem disorder
[Francannet et al., 1990) which was first described by George Fraser in
1962 [Fraser, 1962], who described the main characteristics as
cryptophthalmos (fused upper and lower eyelids), syndactyly and genital
abnormalities. The incidence has been estimated to be 0.43 per 100,000
live births and 11.06 per 100,000 still births [Martinez-Frias et al.,
1994; Comstock et al., 2005]. Survival rates are very low and most
affected individuals die before they reach 1 year of age [Impallomeni et
al., 2006]. It affects males and females equally [Chattopadhyay et al.,
1993]. It is thought to be caused by mutations in two human genes FRAS 1
and FREM 2 [McGregor et al., 2003]. These genes are involved in the
structural adhesion of the skin epithelium to its underlying mesenchyme
[Petrou et al., 2008]. The pathogenesis therefore involves abnormal
epithelium integrity during pre-natal life [Comstock et al., 2005].

A 15 year-old girl with FS presented to Bradford and Airedale
Salaried Dental Services (SDS) complaining of painful lower anterior
teeth. Her parents were first cousins and she was the first and only
child in her family to have FS.

Medical history. She had several features of FS: cryptophthalmos
and anophthalmia with facial asymmetry (Fig. 1), syndactyly (Fig. 2), a
single left kidney, narrow airway in which she required a tracheostomy
fitted for a general anaesthetic for a hysterectomy. She had short
stature for her age and was below the 3rd percentile for height and
weight. She had no signs of developmental delay or learning
difficulties.

[FIGURE 1 OMITTED]

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Dental history. She had previously been seen by other dentists in
the service. On clinical examination (Fig. 3) she was in the full
permanent dentition with congenitally missing 15, 25, 35, 42 and 45. She
had a high vaulted palate. Her occlusion was Class II molars with Class
II division I incisors with an overjet of 13mm, anterior open bite of
4mm and bilateral posterior crossbite. The maxillary incisor 12 was in a
palatal position with 13 buccally placed. Both her and her parents were
not concerned about her dental appearance so no further orthodontic
opinion was sought.

Radiographic examination This confirmed hypodontia and also showed
her third molars to be missing (Fig. 4). All her teeth appeared to have
very short tapered roots with the mandibular anteriors being especially
short (Fig. 5) and presented with grade 3 mobility. She had been seen 4
years previously within the SDS and as a result of the mobility a splint
from 33 to 43 had been fitted in an attempt to protect these teeth from
further trauma. The titanium trauma splint was still in situ but was now
associated with gross calculus, gingivitis and gingival recession. All
her teeth had extrinsic staining but were caries free. She and her
family were warned of the poor long term prognosis of all her teeth,
especially the mandibular anteriors.

[FIGURE 4 OMITTED]

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Treatment

The treatment performed was oral hygiene instruction, removal of
the splint, gross scaling around mandibular anteriors under local
analgesia, reapplication of deficient fissure sealants , and regular two
monthly appointments for supragingival scalings. Periodic use of
chlorhexidine gel for a week at a time instead of toothpaste was used.
She was very co-operative and scored Frankl ++ [Frankl et al., 1962] for
behaviour.

Follow up

Since the removal of the splint she has been reviewed every four
months with scalings and oral hygiene instruction for one and a half
years. The lower anteriors have reduced mobility of grade 1 (Figs. 6 and
7).

[FIGURE 6 OMITTED]

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Discussion

Fraser syndrome is a rare syndrome which is more frequent in
consanguineous parents. This case presented with several of the criteria
for FS and reports hypodontia and short roots. The lower anterior teeth
presented with a poor long term prognosis as a consequence of their
shorts roots and increased mobility. Optimal oral hygiene and
maintenance of good gingival health is essential to maintain their
presence within the dentition.

Using this case and the details from the previous dental case in
the literature both cases report the following oral findings: crowding,
malocclusion, high arched palate, and supragingival calculus. Since this
is the first reported case of hypodontia and short roots these cannot be
concluded as being common findings or associated with the syndrome but
may simply be a coincidence. Further case reports may help to clarify
this. The dental treatment consisted of regular scalings and use of
chlorhexidine gel together with the removal of a splint which inhibited
cleaning of her teeth in this area.

Conclusion

The present case is the first report to describe hypodontia and
shortened roots in Fraser syndrome.